I recall read that there is not a SIOP, but instead of there existing a large number of SIOPs which are, once you get past the fancy names, basically nuclear strike plans (although I think 'options' would be the better word) for practically every country in the world. And yeah, they are always being drafted, reviewed, modified, and burned as the US stockpile, other nations stockpiles, and the global situation changes.
As for what New York would get hit with: my best guess are a few SLBM warheads for the New York harbors, one for the refineries, and probably one or two for downtown Manhatten (mainly the financial district) just to get the final message across. One last ICBM warhead ground-burst for JFK and then, as Stalkere said, leave it to be a humanitarian headache for the surviving US Government(s).
As for Soviet bombers reaching New York of the period: the chances are very good. By the time the bombers reach US territory, the early warning and air defense networks would have been shattered for nearly six-hours. Any interceptor squadrons would have to just fly around and hope they run across a Soviet bomber before it can launch/drop its weapons.
As a hunch, I always suspected the Soviets would send their bombers after any surviving counterforce targets first and then surviving high-priority and medium-priority countervalue targets second. That may mean New York might get a visit from a Bear, or it might not.